[mrkeen]

By making effects explicit, you reap the benefit of being able to write non-effectful code.

Depending on what your language tracked as an effect, you could make your business-logic always terminate, or perform no allocations, if you had effects for Mutation/GeneralRecursion/Allocation.

But no, I certainly don't understand the function->handler control flow here. It has to be handler->function, otherwise you've got two handlers!